Processes for refining hydrocarbon oils by means of benzol derivatives



Patented Nov. 29, 1938 PROCESSES FOR REFINING HYDROCARBON OILS BY MEANS OF BENZOL DER/IVA- TIVES Ernst T'erres, Berlin, Germany, and gosef Moos, New York, and Erich Saegebarth, Jackson Heights, N. Y., assignors to Edeleanu Gesellschaft, m. b. H., a corporation of Germany No Drawing. Application October 25, 1937, Serial No. 170,969

Claims. (01. 196-13) This invention relates to the refining of hydrocarbon oils, suchas mineral oils, coal tar or bituminous coal tar oils, by means of selective solfrom the raffinate and extract solutions the products were found to have the following properities:

vents which have the characteristics of dissolv- Mid-Com ing certain undesirable fractions present in hygf j Rafilnate Extract drocarbon oils for producing oils suitable for tillatc lubricating purposes, and is a continuation in part of our application Serial No. 12,527, filed March Yield by volume 100 63,7

22, 1935, for Process for refining hydrocarbon oils by means of ketones, organic acids, organic $98 7193 III:

anhydrides, organic oxides, alcohols, and ethers. Viscosity index 73.7 97.5 not much is known about the actual Carbon resldue -30 constitution of the individual components present in hydrocarbon oils, it is understood that cuts or fractions which are heavy enough for lubricating stock contain representatives of the aromatic, hydroaromatic and unsaturated groups which are undesirable for lubricating purposes. The removal of these undesirable components by means of suitable selective solvents leaves an undissolved fraction which contains mainly paraffin-like components. These undissolved fractions or rafiinates are identified by greatly improved physical and chemical specifications, such as gravity, viscosity temperature relationship, Conradson carbon and resistance against oxidation.

We have found that benzal acetone hasvery good selective solvent action upon hydrocarbon oils. This solvent dissolves the undesirable fractions of hydrocarbon oils as described above and produces a greatly improved raffinate. In carrying out our invention, we contact the selective solvent with the hydrocarbon oil to be treated in batch or in countercurrent using a mixing and settling equipment or a tower mixer.

The effect of our solvents upon mineral oils may be seen from the following examples.

example, the alcohols.

Example 2 mineral lubricating oil distillate.

The following example illustrates the effect of the admixture of ethyl alcohol as an auxiliary solvent with benzal acetone for extracting a The same dewaxed Mid-Continent distillate as used in Example 1 was extracted with 100% plus 2 50% of a mixture containing 60 volume per cent benzal acetone and 40 volume per cent ethyl alcohol at 75 F. After each extraction the extract was separated from the rafiinate layer and, after recovering the solvents therefrom the products were found to have the following properties:

Example 1 A dewaxed distillate produced from a Mid-Continent crude with properties as shown in the following table, was extracted at 115 F. in two successive treatments with 100% volume (in each treatment) of benzal acetone Rafiinate Extract Yield percent by volume 78. 3 21. 7 LA. P. I 27. 4 9. 8 Saybolt viscosity at 100 F 79. 6 Saybolt viscosity at 210 F. 77.0 Viscosity index- 92 Carbon residue O. 43

( CsHsCI-I: CHCOCH3) It will be seen from the above example that the addition of ethyl alcohol to benzal acetone having a boiling point of 504 F., and a melting decreases the solvent power of the latter sub- Instead of recovering the benzal acetone from the raifinate and extract solutions by distillation, we may employ a different solvent which dissolves only the benzal acetone but not the hydrocarbon fractions. From the solvent mixture containing the additional solvent, and our selective and auxiliary solvents, we may remove the additional solvent either by distillation or by the addition of water or other agents which cause it to become insoluble in our selective and auxiliary solvents.

Other scopes of our invention and the action of the auxiliary solvents is explained in our copending applications Serial Nos. 12,526, 12,528 and 12,529, filed March 22, 1935.

We claim the following as our invention:

1. A process for refining hydrocarbon oils by extracting the latter with benzal acetone at suitable temperatures, to produce separation into two layers, separating the layers containing respectively paraflinic and non-parafiinic constituents from each other and recovering the solvent from the layers,

2. A process for refining hydrocarbon oils by solvent extraction in which benzal acetone is used in presence of an alcohol which is miscible with the selective solvent but which is not miscible, or miscible only to a small degree, with the hydrocarbon oils to be extracted, the addition of said alcohol decreasing the solvent power of the selective solvents.

3. A process of refining mineral oil comprising mixing the oil with benzal acetone as selective solvent and adjusting the temperature to produce a separation into two oil containing phases, separating the phases from each other and recovering the solvent therefrom.

4. A process of refining a mineral oil comprising extracting the oil with benzalacetone as a selective solvent in admixture with an auxiliary solvent to produce a separation into two phases containing relatively paraifinic and non-parafiinic constituents, separating the two phases from each other and recovering the solvents therefrom.

5. A process of refining lubricating oil, containing parafiinic and non-parafiinic constituents, comprising extracting said lubricating oil with benzal acetone as a selective solvent at a temperature of above 108 degrees Fahrenheit, to produce a dissolved layer, consisting of the non-parafiinic oil constituents dissolved in the bulk of the selective solvent, and an undissolved layer, consisting of the paraffinic oil constituents saturated with the selective solvent, separating the dissolved layer from the undissolved layer and removing the solvent from both layers. I

ERNST TERRES. JOSEF MOOS. ERICH SAEGEBAR'I'H. 

